Despite all efforts to minimize error during the fabrication of removable prostheses, accumulated inaccuracy will inevitably add up. Often, this inaccuracy must be managed during the denture insertion with a clinical remount. While the absolute need to perform a clinical remount procedure for every patient has been debated, without a doubt, there are times when a removable case will need to be re-articulated. When a remount is necessary, remount casts will be required.

In the case of a new set of conventional dentures, the dental laboratory technician may have previously fabricated the remount casts, anticipating their potential need as part of the prescribed work (Fig. 1). However, there are several clinical scenarios where the technician may not have provided the remount casts, or the casts are unavailable.

In addition, while these casts are often referred to as “remount” casts, their utility far exceeds their name. For example, remount casts can be incredibly helpful during denture base repairs (Fig. 2) and when evaluating the patient for prosthetic space availability. In contrast, treatment planning for implants (Fig. 3). As a result, the fabrication of remount casts is a skill set many clinicians may want to know.

dental remount casts re-articulated with a facebow transfer jig
Figure 1: The dental technician has fabricated remount casts as a routine part of conventional complete denture fabrication. In this case, the technician has gone one step further and re-articulated the maxillary prostheses and remount cast utilizing a stone facebow transfer jig.
close up of dental remount cast with stone cast
Figure 2: A remount cast was fabricated to maintain the orientation of the denture base fragments during the repair. Although the cast fabrication took additional time during the repair appointment, it provides the benefit of a stable base for this repair and a subsequent repair should it be necessary. In addition, if an error is introduced during the repair procedure, the stone cast will serve as a control. It will allow for a more efficient clinical remount to manage the occlusion. See the details of this repair here.
close up of maxillary denture articulated against a cast of partially edentulous opposing arch
Figure 3: The existing maxillary denture has been articulated against a cast of the partially edentulous opposing arch (left). The remount cast allows the prosthesis to be removed, and the clinical team can evaluate the existing interarch prosthetic space (right).

Clinical Remount Procedure: Techniques and Materials

Depending on the desired use of the cast, the materials and techniques may vary slightly. Regardless of intended use, in the first step, all undercuts on the prosthesis intaglio surface must first be blocked out to preserve the ability to separate the denture and the cast without damage.

Classically, a medium grit pumice slurry (Pumice No.3, Kerr Corp.), modeling clay, or even a wet paper towel would be used for this step (Fig. 4). Another option is to use a silicone material, such as a lab putty Matrix Form 60, Anaxdent North America) (Fig. 4) or even a medium body polyvinyl siloxane impression material Examix Regular Type, GC America (Fig. 5).

The silicone fabrication option has the advantage of preserving detail from the prosthesis intaglio that would otherwise be lost. Suppose silicone, either impression material or laboratory putty, is used. In that case, the material should be adapted well to the intaglio surface of the prosthesis and then allowed to set under 2-3 bar positive pressure (pressure pot, Great Lakes Dental Technologies).

close up of maxillary denture, the undercuts managed with a slurry of pumice (left) and laboratory silicone adapted to the denture intaglio (right)
Figure 4: The undercuts of this conventional maxillary denture have been managed with a slurry of pumice (left). Stone contact with any remaining denture base acrylic should provide stability and rigidity when the denture is seated on the cast. If there is any doubt about the ability to separate the denture from the stone base, additional block-out material should be used. Silicone is an alternative to a block-out material that will wash away like the pumice on the left. In this example, laboratory silicone has been adapted to the denture intaglio and allowed to cure in a pressure pot (right). The flexibility of the silicone will allow the prosthesis to be removed from the remount cast with minimal risk. In addition, the silicone will preserve surface detail from the denture intaglio, which may be helpful for future prosthetic planning. Note that paper clips have been slightly bent and embedded in the laboratory silicone before the silicone goes into the pressure pot. The paper clips provide retention between the stone base and the laboratory putty. A pressure pot is unnecessary when using the pumice approach.
close up of step-by-step remount cast fabrication with impression material
Figure 5: A remount cast is fabricated with medium viscosity impression material. The resulting cast will be stable but may have too much compression or squishiness for precise occlusal adjustment. Still, it will be great for analyzing the available prosthetic space or adding a labial index below.
close up of maxillary denture and remount case with impression material
Figure 6: Introducing a labial index improves the clinician's ability to relate the desired tooth position to the residual ridge.

Once the intaglio has been sufficiently managed, the next step is to create a rigid and stable base (Fig. 7). Generally, a Type II mounting stone (Mounting Stone, Whip Mix) is adequate for the base of the remount cast. A faster setting stone may be desired in specific clinical circumstances where time is critical, such as the need to repair a fractured denture base. Type I mounting plasters often set more quickly than Type II mounting stones but lack the compression strength of Type II stones and experience significantly more setting expansion. As a result, Type I plaster is not an excellent option for improving efficiency. A better option would be selecting a rapid setting, low expansion Type IV stone (Snap-Stone, Whip Mix Corp.)

close up of maxillary denture on dental stone base
Figure 7: After the intaglio has been managed, a dental stone is used to create a rigid base. The stone base allows easy connection to an articulator for post-processing occlusal adjustment or prosthetic space analysis.

In the case of a clinical remount procedure where the occlusion will be selectively adjusted, the denture must be stable on the remount cast. If silicone is used, it is essential to clear the silicone from the denture flange for the prosthesis flange to “bottom out” on the stone portion of the cast (Figs. 8 & 9). This is less of an issue if the cast will be used for space analysis.

close up of maxillary denture showing flange contact with the stone
Figure 8: The denture flange is supported by laboratory silicone in the palate, but the denture flange is in contact with the stone. The denture flange should be covered in less than 1.0 mm of stone. In this image, some of the stone has chipped. If the denture began moving, it might be necessary to remake the remount cast.
close up of maxillary denture showing flange with laboratory silicone removed
Figure 9: The laboratory silicone has been removed from the denture flange in anticipation of contact with the soon-to-be poured stone base. It is essential to watch for labial undercuts that may inadvertently lock the denture to the cast.

Once the stone has been set, the stone base is trimmed in the usual fashion and can be re-articulated in whichever manner the clinician chooses (Fig. 10).

maxillary denture on facebow
Figure 10: The facebow is a common way to articulate the maxillary prosthesis and remount cast.

The Value of the Clinical Remount Procedure in Practice

While the remount cast can undoubtedly be helpful for the identification and management of occlusal inaccuracies with conventional complete dentures as part of a clinical remount procedure at the insertion appointment, the same type of cast may be helpful in a variety of different applications that the clinician may face when working with edentulous patients. The techniques described in this article should provide clinicians with options for efficiently fabricating these casts in the office, thereby preserving clinical efficiency by not relying on their delegation to the dental technician.


Darin Dichter, D.M.D., is a member of Spear Resident Faculty.

References

  1. Firtell, D. N., Finzen, F. C., & Holmes, J. B. (1987). The effect of clinical remount procedures on the comfort and success of complete dentures. The Journal of Prosthetic Dentistry, 57(1), 53-57.
  2. Ansari, I. H. (1996). Simplified clinical remount for complete dentures. The Journal of Prosthetic Dentistry, 76(3), 321-324.
  3. Verhaeghe, T. V., Linke, B. A., Cable, C. E., & Mostafa, N. (2019). Clinical remounting of complete dentures: A systematic review. The Journal of Prosthetic Dentistry, 121(4), 604-610.
  4. Zarb, G. A., Hobkirk, J., Eckert, S., & Jacob, R. (2013). Prosthodontic treatment for edentulous patients: complete dentures and implant-supported prostheses. Elsevier Health Sciences.

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